Electroplating

Name:
Electroplating
Detailed information:
The deposition of a thin layer or coating of metal (e.g., chromium, nickel, copper, silver, etc.) on an object by passing an electric current through an aqueous solution of a salt containing ions of the element being deposited, for example, Cu⁺². The material being plated (usually a metal but often a plastic) constitutes the cathode. The anode is often composed of the metal being deposited; ideally it dissolves as the process proceeds. The thin layer deposited is sometimes composed of two or more metals, in which case it is an alloy. The solution or plating bath contains dissolved salts of all the metals being deposited. Electrolytic cells are used for this process. The anode must be an electrical conductor, but may or may not be of the same chemical composition as the material being deposited, and may or may not dissolve during the process. The purpose of electroplating is usually protection of the base metal from corrosion. Silver is electroplated on copper for economy reasons; plastics may be electroplated for decorative effects.See Electrophoresis; Protective Coating; Electroless Coating; Throwing Power; Current Density.